What Causes Down Syndrome?
Down syndrome is caused when a third extra copy of chromosome 21 gene is created. At this point in time, it is not known what causes this to happen, and the presence of this extra chromosome appears to be random. This abnormal cell division changes the way that the brain, and also the body develops. It happens in the foetus before the baby is born, however it can happen in the sperm before conception in rare cases. A baby can be screened during pregnancy for Down syndrome through a series of blood tests.
|